The invention concerns an open-end spinning machine with a plurality of spinning assemblies disposed next to each other, and with at least one servicing device traveling on a track and capable of being presented to a spinning assembly in need of servicing. The servicing device has at least one servicing instrument or member that is presentable to a structural part of the spinning assembly requiring servicing, for execution of a servicing operation.
It is known that open-end spinning machines may be equipped with mobile servicing devices which execute a partly or fully automatic piecing, cleaning, spool exchange or yarn check. Depending upon the given conditions, the necessary servicing instruments are combined in a single servicing device, or are disposed as a plurality of separately mobile part devices. Since the individual servicing operations, particularly the piecing operation, require that quite specific conditions and spatial relationships be respected, it is necessary that the servicing instruments be presented with great precision to the structural parts of the spinning assembly in question that are to be serviced, so that as far as possible uniform conditions will obtain.
It is known (U.S. Pat. No. 3,990,221 corresponding to German OS No. 2,454,900) that the track for the servicing device can be built in such a way that the servicing device will assume an exactly defined position at each spinning assembly. For this the rails must be made in a special way, and they have to be adjusted. The assembling and adjustment of the rails is a very time-consuming operation. Moreover, that is the risk that after a certain operating time there will be deformations or the like, so that the precision will be lost. Adjustment then has to be repeated on the machine installed in the mill. Moreover, in constructions of this kind, it is only possible exactly to align one respective part of the spinning assembly with a servicing instrument of the servicing device. If the servicing device has a plurality of servicing instruments or members that are presented to different structural parts of the spinning assembly, there are more difficulties that can only be mastered by a very precise maintenance of manufacturing and assembly tolerances, both of the spinning assembly and of the servicing device.
The invention is intended to create an open-end spinning machine of the specified type in which there is no need for such close tolerances in presentation of the individual servicing instruments or members to the structural parts to be serviced, in the spinning assembly. This problem is solved in that each servicing instrument is provided with an aligning element that, in presentation of the servicing instrument to the structural part of the spinning assembly that requires servicing, will engage a guide element disposed fixedly in an adjustable position with reference to the structural part, on the spinning assembly or on the machine frame.
In this arrangement it is provided that each servicing instrument will be centered on this structural part by means of the aligning elements and the guide elements in presentation to the part that is to be serviced, so that thereby the effect of inaccuracies in assembling and/or manufacture will be offset. There is the advantage that each servicing instrument or member that cooperates with a structural part of the spinning assembly can be precisely aligned so that also the disposition of the servicing instruments and member inside the servicing device and the disposition of the individual structural parts in the spinning assembly can be managed without excessively close tolerances. Adjustment of the guide elements can be undertaken easily with use of appropriate templates in the manufacturing plant. This adjustment, in assembling the open-end spinning machine at the mill, is not intended to be further changed. However, according to preferred contemplated embodiments it is possible without much effort to undertake a new precise adjustment if the machine is changed over, or if repairs are to be made.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.